By: newkid

newkid — Mon, 05 Jul 2010 20:37:46 +0000

WITH  d AS (SELECT t1.pk pk1,t2.pk pk2,DENSE_RANK() OVER (ORDER BY t1.pk) rn,COUNT(DISTINCT t1.pk) OVER() cnt
             FROM t1,t2
            WHERE t2_compare BETWEEN t1_compare-2 AND t1_compare+2
            )
    , m AS (SELECT pk1,pk2,rn,cnt FROM d
             UNION ALL
            SELECT DISTINCT pk1,NULL,rn,cnt FROM d
           )
,t(rn,match_path,match_cnt,cnt) AS (
SELECT rn,TO_CHAR(pk1)||'-'||TO_CHAR(pk2),(CASE WHEN m.pk2 IS NULL THEN 0 ELSE 1 END),cnt
  FROM m 
 WHERE rn=1
UNION ALL
SELECT m.rn,t.match_path||','||m.pk1||'-'||m.pk2,t.match_cnt + (CASE WHEN m.pk2 IS NULL THEN 0 ELSE 1 END),t.cnt
  FROM t,m
 WHERE t.rn

Comments on: How to find matched rows between 2 tables based on required matching criteria in a SQL statement

By: newkid